Answer:
x=7
Step-by-step explanation:
Solve.
7x-5x-3=x+4
Calculate like terms.
7x-5x=2x
Rearrange.
2x-3=x+4
Apply inverse addition.
2x-3+3=x+4+3
2x=x+7
Isolate 2x by subtraction.
2x-x=x-x+7
x=7
Since E is the midpoint, DE and EF are the same length.
Set the equation DE and EF equal to each other and solve for x.
2x + 4 = 3x - 1
x = 5
Then plug in 5 to find the length.
DE = 2(5) + 4 = 14
EF = 3(5) - 1 = 14
DF = DE + EF = 28
7 6/12 is already in mixed number form, but it can be simplified to 7 1/2
Hope this helps you
-AaronWiseIsBae